Here are some possibilities for good day trips from Zadar:
Kornati Islands National Park
This sprinkling of 147 rocky islands and islets is one of the Adriatic's most beguiling sights.
Paklenica National Park
Hiking, rock climbing or a gentle mountain walk are all on offer here, only 45 minutes by car or bus.
There are some great beaches and great eating on this island where sheep outnumber people.
Regular boats whisk you to this long island that is never overrun with tourists.
Plitvice Lakes National Park
It's a long drive (about 2 hours) but doable and what a reward at the end!
Krka Waterfalls National Park
Only about an hour away and here's another National park with more lakes and falls.
This small town is right near the sandy Soline Cove, perfect for swimming.